screensaver won't activate

Try System->Preferences->Screensaver

Select a screensaver, (I think the default is "Blank Screen" which your computer might be set to now) then select a timeout for your screensaver to start and select which of the check boxes you'd like on the bottom.

If you do this, it should be permanent.

When do applications>systems I don't have a preferences>screensaver. Do have screensaver under settings>screensaver and go into itit says screensaver preferences,select what want,set time and activate when computer idle and never goes to it. A couple of days a month it will go to blank screen but next few days never activates. Then a week later will go to blank screen most of day,then back to not.

No, its System->Preferences->Screensaver.

Here's a screenshot of where "Screensaver" is located:
http://www.doztech.net/wp-content/pictures/LearningUbuntuHowtochangetheScreensaver_6796/image_thumb.png

Tell me if you can find the screen, then change the settings because if it still does not work you might need help with "cron" (a task scheduler utility) or 'gnome-screensaver" the package itself.

That is sure not what my screen looks like,more windowy looking. Several times have read to go into something like the System>Preferences>screensaver but I don't have Preferences under system,why not. I have the screensaver preferences box and can select one I want and activate when idle but it doesn't do it. I looked and I have gnome screensaver 2.28.0 oubuntu 3.5 installed. I did find a task scheduler utility under gnome desktop files and downloaded it so see what happens now. My screen saver is under settings>screensaver. Thanks for your help,be patient with me,still trying to learn.

Hey no problem, I'm happy to help.

Can you check what version of Ubuntu you have? Run the terminal by clicking Applications -> Accessories -> Terminal. In a terminal type in "lsb_release -a" (without the quotes). Then type in the results back here. I have a hunch that you are using a different GUI than Gnome, which is why it is harder for me to explain how to find the screensaver settings.

This is how Gnome looks like:
http://en.wikipedia.org/wiki/File:Ubuntu_9.10.png

and KDE (another GUI) looks like:
http://en.wikipedia.org/wiki/File:Kubuntu910.png

and XFCE (another GUI) looks like:
http://en.wikipedia.org/wiki/File:Xubuntu-karmic.png

Here's my plan:
I am going to find out what exactly operating system you are using.
Try to get you to configure your screensaver correctly.
And if that fails, try to fix cron or gnome-screensaver on your computer.

Also, you probably don't need a new task scheduling utility you installed, since cron is arguably the king of task schedulers.

Ok did that No LSB modules are availiable
                   Distrubutor ID Ununtu
                   Description Ubuntu 9.10
                   Release 9.10
                   Codename Karmic

did the other thing and mine is the XFCE desktop,definitely,doesn't look like the windows type layout. I get the screensaver box and has a lot of them to select,got the fiberoptic lite selected and have set for 3 min and to activate when computer idle then click close. It has worked some in the past,think about every time it timed out but all of a sudden it quit but will do blank screen a couple of times a month seems like. I didn't have the top and bottom menu bars but could do Alt F2 and run xfce4-panel and get them but had to do each time booted up but got that fixed,put the xfce4-panel in startup list so it is working. Do I have the cron installed,is it a automatic thing when install?? Thanks very much for helping me,really appreciate it.

Hey poppy812, sorry for the delay. I did some digging and other people have had this problem too. You need to update your computer (specifically gnome-screensaver), then restart. Run Applications -> System -> Update Manager to do the update.

A bug was found, it seems just before Christmas, with gnome-screensaver and was fixed with an update.

Here are some of the website I was digging through if you are interested:

http://www.ubuntu.com/usn/USN-866-1
http://bugzilla.xfce.org/show_bug.cgi?id=5927
https://bugs.launchpad.net/ubuntu/+source/xfce4-session/+bug/493573

The reason it took me a day to reply is because I downloaded Xubuntu myself and tested it. I got the same screensaver problem as you, so I can confirm it.

Tell me how the update goes. If this doesn't work, I can create a bug report.

I did the update,think I did anyhow,but it is still not working. Guess wait till 10.4 comes out and see what happens. How can I change to gnome from xfce and get the windows look desktop. Thanks again for your help,you guys are great. Did the download on manual for 10.4,have to read through it and see what can do. Thanks again.

Waiting until 10.4 comes out is always your best bet since things can be fixed implicitly and its a LTS so the developers are focusing on fixing bugs whether they are subtle bugs or 'show stoppers'.

If you want to change to Gnome, you simply need to download Ubuntu 10.4 from Ubuntu.com this Thursday. I personally can't wait for 10.4 :)

Can a web browser and/or flash player elements in web pages intercept with the activities of gnome screensaver? I am experiencing the same odd behavior and usually I got web browser open then this problem becomes apparent. What's strange though is that after failure to activate screensaver magic if I suspend to ram and wake up afterwards then screensaver starts to work.